Chair with folding tablet arm

ABSTRACT

A CHAIR WITH A FOLDING TABLET ARM ESPECIALLY ADAPTABLE FOR INSTALLATION ON RETRACTABLE BLEACHERS WHERE THE TABLET ARE IS ARRANGED FOR MOVEMENT SERIALLY THROUGH THREE GENERALLY ORTHOGONALLY RELATED QUADRANTS, THE FRAME BEING EQUIPPED WITH LOCK MEANS FOR MAINTAINING THE TABLET ARM IN A STORED POSITION, AND FURTHER SERVING AS A BUMPER WHEN THE CHAIR IS COMPLETELY COLLAPSED AND RETRACTED WITHIN A STORAGE RECESS IN THE BLEACHER.

March 7 A. L. VAN RYN ,5?

' CHAIR WITH FOLDING TABLET ARM Filed march 24, 1969 3 Sheets-Sheet 1 ATTORNEYS Mmmh Z; EQTE VAN W I 3,5?,2?@

' CHAIR WITH FOLDING JJABLET ARM Filed March 24, 1969 s Sheets-Sheet a INVENTOR Amman L. Van Wyn ATTORNEYS A. L... VAN R'YN CHAIR WITH FOLDING TABLET ARM 3 Sheets-Sheet Filed March .24, 1969 1OR Ar-thw L. Van WV 5 Y E N m w A B @au/m I I In}! E 7 i United States Patent 3,567,276 CHAIR WITH FOLDING TABLET Arthur L. Van Ryn, Grand Rapids, Mich., assignor to American Seating Company, Grand Rapids, Mich. Filed Mar. 24, 1969, Ser. No. 809,531 Int. Cl. A471) 39/ 00 U.S. Cl. 297-162 8 Claims ABSTRACT OF THE DISCLOSURE A chair with a folding tablet arm especially adaptable for installation on retractable bleachers where the tablet arm is arranged for movement serially through three generally orthogonally related quadrants, the frame being equipped with lock means for maintaining the tablet arm in a stored position, and further serving as a bumper when the chair is completely collapsed and retracted within a storage recess in the bleacher.

BACKGROUND AND SUMMARY OF THE INVENTION In contrast with the prior art, the inventive chair makes use of a linkage mechanism for the various degrees of movement, rather than just one arm that swings in an arc; the tablet arm is arranged to be tightly held against the front leg of the chair when the chair is folded, and this condition does not touch the surface of the bleacher platform or pedestal, retracting into the next bleacher with the chair, making the unit advantageously compact and rugged.

DETAILED DESCRIPTION 'FIG. 1 is a top view of a two chair unit with the right tablet arm (right relative to an occupant) folded in the stored position and with the left tablet arm in the position to be used by the occupant;

FIG. 2 is a front perspective view of the two chair unit with the right tablet arm in the stored position, while the left tablet arm is turned, ready to be raised; the right seat being raised to be out of the line of vision;

FIG. 3 is a similar front perspective view with the right tablet arm up and the left tablet arm in the position to be used by the occupant, a portion of the near tablet arm being cut away to give a full view of the further one;

FIG. 4 is a fragmentary side view of the front leg of the chair with the tablet arm in the folded position showing the linkage;

FIG. 5 is a perspective view of the two chair unit in the raised folded position used when sweeping is to be done, shown here to point out the five points of contact with the platform when the chairs are down;

FIG. 6 is a fragmentary side view of the right front leg of the chair with the tablet arm in the position for use;

FIG. 7 is a perspective view of the two chair unit folded down on the platform ready for storage;

FIG. 8 is an exploded view of the parts of the tablet arm assembly; and

FIG. 9 is a fragmentary side view of a retracted bleacher section with a chair unit folded inside of it.

The numeral 10 designates a chair unit useful as a foldaway stadium chair, with the unit equipped with a plurality of backs 11 and the same number of seats '12. Usually, the unit will be made up of one, two, or three backs and seats. Normally the seats 12 are about one inch narrower than the backs 1.1, and a block 13 is provided to connect the seat to the left front leg 14, allowing space for a folding tablet arm mechanism 15 to be folded and raised between the seat and the leg.

'ice

The tablet arm T assumes the following positions in its travel: the stored position 16, a turned out position 17, a raised position 18, and finally a position 19 of operation or use wherein the same is folded over an arm rest 20 for use by the occupant. These four positions are seen in FIGS. 2 and 3.

The folding tablet arm mechanism 15 employs the use of two links, a short link 21 and a longer link 22. Reference to FIG. 8 reveals that the shorter link 21 (as seen in the central left hand portion of FIG. 8) is equipped with an offset, this being employed to clear a bolt head in the particular environment illustrated. Each link is pivotally coupled to the frame at the corresponding lower end thereof as by clamp plates 23 and 24. In the exploded view illustrated in FIG. 8, these plates are found immediately to the right of the shorter link 21. The longer link 22 is also seen closely related to the clamp plates 23 and 24, and the assemblage is also readily perceived by a consideration of FIG. 6. In FIG. 6, however, the plate 24 is masked by the plate 23. The plates 23 and 24 are identical except that the plate 24 has one square hole, the plates 23 and 24 being attached to the side of the right front leg 25 (see, for example, FIG. 3).

The upper ends of the links (when the tablet arm T is in the operational position seen in FIG. 6) are pivotally connected to one leaf 26 of a hinge member 27. As can be appreciated from FIG. 8, the leaf 26 is narrow. The links 21 and 22, in company with the leaf 26 and clamp plates 23 and 24, provide essentially a parallelogramtype linkage, operating on the principle of parallel bars to swing the tablet arm from a vertical stored position 16 to a horizontal position of use .19, as best seen in FIGS. 4 and 6.

When the tablet arm T is swung out from the position 16 to the position 17 (see FIG. 2), it forces the hook arm 29 of a fork-type locking mechanism 28 down into the unlocked position as is seen best in 'FIGS. 3 and 6. However, when the tablet arm is folded again and swung from the turned out position 17 to the stored position 16, it strikes the upwardly pointing arm 30 of the fork mechanism 28, forcing the hook arm 29 up into the locked position. There, the mechanism 28 holds the tablet arm T tightly against the leg 25 as in FIGS. 2 and 4.

When the tablet arm T is locked behind the locking mechanism 28 (as in the case of the showing at 16 in FIG. 2), the chair may be folded and lowered into the prone position as in FIGS. 7 and 9. At that time, the chair rests upon five points of contact with the platform or pedestal of the bleachers. These points (best seen in FIGS. 5 and 9) include a plurality of small rubber bumpers 31 and 32. The rubber bumpers 31 are smaller and are positioned near the front edge of the seat, while the two large bumpers 32 are located beyond the center of the seat. The fifth point of contact is provided by the hooked surface 29 of the locking mechanism 28.

Reference is now made to the exploded view in FIG. 8 where it is seen that the tablet arm assembly consists of a plurality of parts besides the rubber bumpers 31 and 32 which are illustrated therein.

The tablet arm T is attached to the hinge 27 by several screws 33 extending through holes in the wide leaf 34 of the hinge 27. The barrel 35 of the hinge fits into a notch 36 provided in the edge of the tablet arm. The barrel 35 is equipped with a small stop block 37 (see FIG. 8) which prevents the hinge from opening too far when the tablet arm T is in the turned out position 17 or the raised position 18. Two plastic spacers 38 fit into holes in the wide leaf 34 and protect the arm rest 20 from being scratched by the hinge. A notch 39 is cut into the narrow leaf 26 of the hinge 27 to provide clearance for the tablet arm mechanism when it swings into the down positions as designated by the numerals 16 and 17. In the illustration given, this is advantageous, since otherwise the leaf 26 would strike the chair linkage on the right, as seen in FIGS. 2, 7 and 9.

The short link 21 is attached to the narrow leaf 26 by means of a shoulder rivet 42 extending through the hole 41 in the leaf 26. A corresponding hole 21a is provided in the short link 21. The longer link 22 is attached to the narrow leaf 26 by being mounted at its upper end on a shaft 43 (as seen in FIG. 8). A snap fastener 44 is provided to releasably lock this assembly, and the shaft 43 is attached to the leaf 26 via the hole 45 as by welding or riveting.

The lower end of the short link 21 is mounted on a friction pivot 46 which has a Belleville friction washer, a slightly spherical spring washer 47 mounted on its shoulder 48. A spacer washer 49 is placed on the shaft of the pivot 46, and pivot 46 is threaded through the top hole 50 of the right hand clamp plate 23. The pivot is also inserted through the right front leg 25 so that the square end 51 of the pivot 46 protrudes just enough to slip into the square hole 52 of the left hand clamp plate 24. A Sems screw 53 (a screw with an external tooth lock washer permanently mounted on it) with a fiat washer is threaded into the end of the friction pivot 46. During initial assembly, this is a loose threading, the tightening occurring later. A hex head bolt 55 is threaded through the lower rear hole 56 of the two clamp plates and the front leg. The bolt 55 has a hex nut 57 threaded on italso not tightened. Lastly, the projections 58 on the lower link 22 can be snapped into the remaining holes 59 of the two clamp plates 23 and 24. Once this is done, the screw 53 and nut 57 are tightened securely together.

The locking mechanism 28 is attached to the front leg 25 by inserting the threaded portion 60 through the lower hole of the right front leg 25 from the occupants left, so that the arm 30 of the fork mechanism points upward. A Belleville friction washer 61 is used to keep the locking mechanism from turning freely, and a hex nut 62 is added.

The rubber bumpers 31 and 33 are mounted on the bottom of each seat 12 in the places indicated as in FIG. 5, with suitable thread cutting screws 63 and 64 and washers 65.

I claim:

1. In combination, a support structure, a folding tablet arm chair comprising a frame equipped with a generally vertically-extending back when the frame is oriented to support a person, said frame being coupled along the rear side to said support for pivotal collapse, a seat mounted on said frame for movement between generally horizontal and vertical positions, a tablet arm operably associated with said frame, and linkage pivot means interconnecting said frame and tablet arm for moving said tablet arm serially through three generally orthogonally related quadrants and with the tablet underlying said seat, when the frame is collapsed.

2. The chair of claim 1 in which said seat is equipped. with bumper means to partially support said chair when said frame is collapsed.

3. The chair of claim 2 in which said frame is equipped with lock means for said tablet arm when the latter is in stored position, said lock means being arranged and constructed to provide additional bumper means to support said chair.

4. The chair of claim 1 in which said linkage pivot means includes a generally parallelogram type linkage, said parallelogram type linkage having first and second links pivotally coupled to said frame at corresponding ends thereof and with the other ends operatively associated with said tablet arm, and a hinge member interposed between said other link ends and said tablet arm to provide two of the three quadrant movements.

5. The chair of claim 4 in which said hinge member includes two leaves, one of said leaves being secured to said tablet arm and the other of said leaves being pivotally coupled to said link other ends, one of said links being longer than the other and coupled to said other leaf a spaced distance forwardly of the coupling thereto of the other link, said hinge being equipped with means limiting the pivotal opening movement thereof.

6. The chair of claim 1 in which said frame is equipped with a fork lock mechanism pivotally secured to said frame adjacent the lower end thereof, said tablet arm being operative to be confined between the prongs of said fork mechanism.

7. The chair of claim 1 in which said chair is equipped with an arm rest extending in partial supporting relation to said tablet arm when the latter is in operational position, and bumper means on said tablet arm to prevent the latter from scratching said arm rest.

8. The chair of claim 1 in which said frame is equipped with pivotally mounted fork means to selectively lock said tablet arm in stored position.

References Cited UNITED STATES PATENTS 7/1965 Brown 297-162X 5/1969 Brunskole 529X US. Cl. X.R. 297248 

